Replaceable probe apparatus for probing semiconductor wafer

ABSTRACT

A probe apparatus is provided with a plurality of probe tiles, an interchangeable plate for receiving the probe tiles, a floating plate being disposed between the respective probe tile and a receiving hole on the interchangeable plate, and a control mechanism providing multi-dimensional freedom of motions to control a position of the probe tile relative to the respective receiving hole of the interchangeable plate. A method of controlling the floating plate is also provided by inserting a pair of joysticks into two respective adjustment holes disposed on the floating plate and moving the pair of joysticks to provide translational motions (X-Y) and rotational (theta) motion of the floating plate, and turning the pair of jack screws clockwise and counter-clockwise to provide a translational motion (Z) and two rotational (pitch and roll) motions of the floating plate.

CROSS-REFERENCE TO RELATED APPLICATION

This patent application claims the priority of U.S. Provisional PatentApplication Ser. No. 60/940,242, filed on May 25, 2007, and subjectmatter of which is incorporated herewith by reference.

This patent application is also related to U.S. Utility PatentApplication Ser. No. 09/730,130, filed on Dec. 4, 2000, now issuedpatent 6,586,954; U.S. Utility Patent Application Ser. No. 10/601,764,filed on Jun. 23, 2003; U.S. Utility Patent Application Ser. No.09/021,631, filed on Feb. 10, 1998, now issued patent 6,201,402; U.S.Utility Patent Application Ser. No. 10/607,768, filed on Jun. 27, 2003;U.S. patent application Ser. No. 10/383,079, filed on Mar. 6, 2003; U.S.Utility Patent Application Ser. No. 10/809,051, filed on Mar. 25, 2004;U.S. Utility Patent Application Ser. No. 11/216,757, filed on Aug. 31,2005; subject matter of which are incorporated herewith by references.

FIELD OF THE INVENTION

The present invention relates generally to semiconductor test equipment,and more particularly, to a probe apparatus used in semiconductor testequipment for electrically probing devices on a semiconductor wafer.

BACKGROUND OF THE INVENTION

The semiconductor industry has a need to access many electronic deviceson a semiconductor wafer. As the semiconductor industry grows anddevices become more complex, many electrical devices, most commonlysemiconductor devices, must be electrically tested, for example, forleakage currents and extremely low operating currents. These currentsare often below 100 fA. In addition, the currents and devicecharacteristics are often required to be evaluated over a widetemperature range to understand how temperature affects a device,thereby having controllable device characteristics. To effectivelymeasure at currents below 100 fA, a measurement signal must be isolatedfrom external electrical interference, leakage currents through thedielectric material, parasitic capacitance, triboelectric noise,piezoelectric noise, and dielectric absorption, etc.

Additionally, due to the wide variety of die pitches (referring to thespacing between adjacent devices on a die/wafer or the correspondingspacing between adjacent probe tiles on a base plate), users need theflexibility of reusing probe tiles in a variety of base plates. Thesebase plates match different die pitches. Die pitch relates to the sizeof a die. The size of a die pitch may vary, for example, from 10 mm² to30 mm², etc. Further, the shape of a die pitch may vary as well, forexample, a rectangular shape, a square shape, etc.

At present, semiconductor test equipment is designed such that a userhas to use different probe tiles (or sometimes referring to as “probecards”) if the size or shape of die pitches on a die/wafer is different.

Thus, it is desirable to have a probe apparatus that allows theflexibility of reusing probe tiles. Further, it is desired that externalelectrical interference, leakage currents through the dielectricmaterial, parasitic capacitance, triboelectric noise, piezoelectricnoise, and dielectric absorption are significantly reduced oreliminated.

SUMMARY OF THE INVENTION

To solve the above and the other problems, the present inventionprovides a probe apparatus for testing semiconductor devices on a wafer.

In one embodiment of the present invention, the probe apparatuscomprises:

-   -   an interchangeable plate having at least one receiving hole;    -   at least one probe tile to be placed in the at least one        receiving hole;    -   at least one floating plate, the at least one floating plate        being disposed between the respective probe tile and the        receiving hole; and    -   a control mechanism providing multiple dimensional freedom of        motions to control a position of the probe tile relative to the        respective receiving hole of the interchangeable plate.

Still in one embodiment of the present invention, the floating plateincludes at least one hold-down slot for receiving a hold-down screw tomount the floating plate onto the interchangeable plate, at least onejack screw, and at least one adjustment hole for receiving a “joystick”type of rod.

Further in one embodiment of the present invention, themulti-dimensional freedom of motions include translational (X-Y) motionsand rotational (theta) motion controlled by the “joystick” type of rod,and a translational (Z) motion and pitch and roll motions controlled bythe jack screw. In one embodiment, there are two jack screws and two“joystick” type of rods.

Yet in one embodiment of the present invention, the probe tile is aself-contained unit and removable or replaceable from the respectivereceiving hole. Multiple devices on a wafer placed under theinterchangeable plate can be tested independently or simultaneously, anddifferent sets of devices on the wafer can be tested after replacing atleast some of the probe tiles.

These and other advantages of the present invention will become apparentto those skilled in the art from the following detailed description,wherein it is shown and described illustrative embodiments of theinvention, including best modes contemplated for carrying out theinvention. As it will be realized, the invention is capable ofmodifications in various obvious aspects, all without departing from thespirit and scope of the present invention. Accordingly, the drawings anddetailed description are to be regarded as illustrative in nature andnot restrictive.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an exploded view of one embodiment of a probeapparatus generally in accordance with the principles of the presentinvention.

FIG. 2 illustrates a partial, close-up view of one embodiment of a probeapparatus generally in accordance with the principles of the presentinvention.

FIGS. 3A and 3B illustrate a side elevation view and a cross-sectionalview of a “joystick” motion of a “joystick” type of rod whichmanipulates and provides multiple dimensional freedom of motions of theprobe tile relative to the respective receiving hole of theinterchangeable plate generally in accordance with the principles of thepresent invention.

FIG. 4 illustrates one embodiment of an interchangeable plate and aprobe tile disassembled from the interchangeable plate of the probeapparatus generally in accordance with the principles of the presentinvention.

FIG. 5 illustrates one embodiment of the floating plate mounted on oneof the receiving holes of the interchangeable plate of the probeapparatus generally in accordance with the principles of the presentinvention.

FIG. 6 illustrates one embodiment of a probe tile mounted on thefloating plate as shown in FIG. 5.

FIGS. 7 and 8 illustrate one embodiment of the probe tile mounted on thefloating plate being manipulated by one or two “joystick” type rodsgenerally in accordance with the principles of the present invention.

FIG. 9 illustrates one embodiment of the floating plate generally inaccordance with the principles of the present invention.

FIG. 10 illustrates a top view of one embodiment of a probe apparatushaving a probe tile being mounted on the interchangeable plate in aprobe testing environment generally in accordance with the principles ofthe present invention.

FIG. 11 illustrates a bottom view of one embodiment of a probe apparatusas shown in FIG. 10 generally in accordance with the principles of thepresent invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

In FIGS. 1-11, a probe apparatus 100 generally in accordance with theprinciples of the present invention includes an interchangeable plate102 having a plurality of probe tile receiving holes 104, a plurality ofreplaceable probe tiles 106 (one is being shown in FIGS. 1-2) to beplaced in the receiving holes 104; and a plurality of floating plates108 (one is being shown in FIGS. 1-2). The floating plate 108 is mountedon the respective receiving hole 104 between the respective probe tile106 and the receiving hole 104.

As shown in FIGS. 1-9, the floating plate 108 includes at least oneretaining slot 110 (or referred to as “hold-down slot”) for receiving ahold-down screw 111 to mount the floating plate 108 onto theinterchangeable plate 102, a pair of jack screws 112, at least oneadjustment hole 114 for receiving a “joystick” type adjustment rod 116.The floating plate 108 is disposed between the respective probe tile 106and the receiving hole 104.

As shown in FIGS. 3A-3B, 5, and 7-8, a control mechanism 120 providesmultiple dimensional freedom of motions to control a position of theprobe tile 106 relative to the respective receiving hole 104 of theinterchangeable plate 102. To afford full positioning capability ofindividual probe tiles, the control mechanism 120 controls at least 6degrees of freedom of movement. In one embodiment, two adjustment rods116, such as a “joystick” type of rod, are used to provide twotranslational (X & Y) motions and one rotational (theta) motion, whichare not shown but commonly understood by person skilled in the art. Whenthe pair of joysticks 116 are moved in unison, the translations on aprobe tile match the direction of the joysticks 116. The theta rotationis accomplished by moving the pair of joysticks 116 in oppositedirections.

Further in the embodiment shown in FIG. 5, the pair of jack screws 112are used to provide the remaining translational (Z) motion and tworotational (pitch and roll) motions. The jack screws 112 are paired onopposing sides of the probe tile 106. In one embodiment, running all thejack screws 112 up (e.g. counter-clockwise) raises the probe tile,whereas running all jack screws 112 down (e.g. clockwise) lowers theprobe tile. By running one of a pair of opposing jack screws 112 up andthe other down, the probe tile can be tilted, i.e. pitch and roll.

Also, the floating plate 108 may be used as a spring to maintain apreload on the jack screws 112 and provide friction to maintain theprobe tile position during a test.

The probe tile 106 is a self-contained unit which is mounted on thefloating plate 108 by mounting the probe tile 106 via mounting holes 113as shown in FIG. 5. The probe tile 106 is removable from the floatingplate 108 and can be replaced by another probe tile 106. Multipledevices on a wafer placed under the interchangeable plate 102 can betested independently or simultaneously. The probe tiles are removableand replaceable, and different sets of devices on the wafer can betested after removing and replacing some of the probe tiles 106.

Other features and advantages of the present invention may include thefollowing:

1) High mechanical tolerance.

2) Controllable characteristics affected by many factors, such astemperature, limited connections/bond pads and device real estate on awafer.

3) Flexible testing capability.

4) Interchangeable probe plate, float plates for lateral motion,pitch/roll adjustments between the probe plate and the probe tile.

5) Self-contained probe tile.

6) Features described in the related patent applications mentionedabove.

7) Scalability

8) High Testing Precision

From the above description and drawings, it will be understood by thoseof skilled in the art that the particular embodiments shown anddescribed are for purposes of illustration only and are not intended tolimit the scope of the present invention. Those of skilled in the artwill recognize that the present invention may be embodied in otherspecific forms without departing from its spirit or essentialcharacteristics. References to details of particular embodiments are notintended to limit the scope of the invention. For example, it isappreciated that in other embodiments, one joystick or more than twojoysticks can be provided without departing from the scope of thepresent invention.

1. A floating plate for mounting a probe tile to a probe apparatus,comprising: at least one hold-down slot receivable of a hold-down screw;and a control mechanism including at least one jack screw; and at leastone adjustment hole receivable of a “joystick” type of rod. 2-6.(canceled)
 7. The floating plate of claim 1, wherein the at least onejack screw comprises a pair of jack screws placed on opposing sides ofthe floating plate.
 8. The floating plate of claim 1, wherein the atleast one adjustment hole comprises a pair of adjustment holes placed onopposing sides of the floating plate.
 9. The floating plate of claim 1,further comprising a hole receivable of a portion of a probe tile. 10.The floating plate of claim 9, wherein the hole is disposed in a centralregion of the floating plate.
 11. The floating plate of claim 9, furthercomprising at least one mounting hole mountable of a probe tile.